Fritz otte



(No Model.)

F. OTTE. SCREW PROPELLEB..

No. 517.233. Patented Mar.-27, 1894.

Wig/www.

FRITZ OTTE, OF ALTONA, GERMANY.

SCREW-PROPELLER.

SPECIFCATON formingpartof Letters Patent O. 517,233, dated March 27,1894.

Application tiled July 12, 1893. Serial No. 480,248. (No model.)

To a/ZZ whom t may concern:

Be it known that I, FRITZ OTTE, of 59 Lohmhlenstrasse, Altona, in theGerman Empire, have invented a new and useful Screw- Propeller withBlades which Can be Adjusted during Rotation, of which the following isa specification, reference being had therein to the accompanyingdrawings.

The object of this invention is ascrew pro` peller, the blades of whichcan be adjusted, or turned to the required pitch, while propelling orrotating, by mere motion of the propeller shaft in the direction of itsaxis, and so that not only the speed of the vessel can be regulatedthereby, but that its direction of motion can be reversed without in anyway altering the speed or direction of motion of the engine, whilepermitting easy handling of the vessel.

Figure l of the drawings is a plan View; Fig. 2 a transverse sectionthrough the boss and shaft, and Figs. 3 and 4 longitudinal sectionsthrough the boss at right angles to each other.

Each blade a of this propeller is at its rootend provided with a roundflange b so inserted into the two parted hollow boss that the blade acan turn on its axis vertically to the propeller shaft d. On each [iangeface near the circumference is provided a lug e working each in a groovef formed on two opposite sides of a block g fixed on the propeller shaftd and capable of sliding in the boss in the axial direction of theshaft. Assuming that the shaft is protruded axially to its farthestpoint to the right, then the grooves f will hold the lugs c in such aposition that the pitch angle of the blades is a maximum, and forquickest forward motion of the vessel. If the shaft during motion ispushed from the extreme right to the left, the grooves f will carry thelugs e with them so that the blades are turned vertically to the shaft,and the angle of the propeller-surface, or the pitch, is diminished, andthe speed of the vessel diminished. In the medium position thebladesstand s'o that the angle of the blades is nothing, and the vessel standsstill. If the shaft is pushed from the medium position farther to theleft, the angle will become negative; that is, the propeller blades willform lefthand screw tread instead of right hand screw tread, and thevessel will go astern. The more the shaft is pushed to the left, thegreater becomes the angle of the blades and the greater the pitch, andhence also the speed for going astern.

What I claim, and desire to secure by Letters Patent of the UnitedStates, is-

In combination with the shaft d, the block 6o g fixed thereto and havinggrooves f in opposite faces, the boss c carried by the shaft, thepropeller blades b pivotally secured within the boss and projections eengaging the grooves, substantially as described.

In witness whereof I have hereunto set my hand in presence of twowitnesses.

FRITZ OTTE.

Witnesses:

PAUL FISCHER, JOHN SALowsKI.

